Railway car mover



Feb. 11, 1964 I T. D. STEWART 3,120,741

RAILWAY CAR-MOVER Origmal Filed Oct. 28, 1958 5 Sheets-Shet 1 Speed Control and Reverse Unit INVENTOR. Thomas Dale Stewart H/S ATTORNEYS T. D. STEWART RAILWAY CAR MOVER Feb. 11, 1964 5 Sheets-Sheet 2 Original Filed Oct. 28, 1958 R m m V m Thomas Dale Stewart Mil Maw- H/S A TORNEYS Feb. 11, 1964 T. D; STEWART 3,120,741

RAILWAY CAR MOVER Original Filed Oct. 28, 1958 5 Sheets-Sheet 3 5 no t v m .J o

o N \I ,9, INVENTOR cu Thomas Dale Stewart Speed Feb. 11, 1964 RAILWAY CAR MOVER Original Filed oct. 28, 1958 5 Sheets-Sheet 4 Thomas Dale Stewart HIS ATTORNEYS Feb. 11, 1964 T. n. STEWART 3,120,741

RAILWAY CAR MOVER ori inal Filed Oct. 2a, 1958 5 Sheets-Sheet 5 Speed Control and Reverse Unit IN VENTOR. Thomas Dale Stewart w IFW M HIS ATTORNEYS United States Patent 3,12tl,741 RAILWAY CAR MOVER Thomas Dale Stewart, New Kensington, Pa., assignor to Movet Industries, Incorporated, New Kensington, Pin,

a corporation of Pennsylvania Original application Oct. 28, 1958, Ser. No. 770,103, new Patent No. 2,989,967, dated June 20, 1961. Divided and this application Sept. 26, 1960, Ser. No. 63,937

2 Claims. (Cl. 6tl97) The present application relates generally to a railway car mover and more particularly to a self-propelled traction device adapted for moving Wheeled railway cars of a type in which each of two flanged wheels located at opposite sides to one another on the car are provided with a solid axle therebetween.

Car mover devices are designed to provide a very useful function in commercial plants, along coal mine sidings, and at dockside sites wherein railroad cars must be shifted about from time to time in the loading and unloading operation. Shipping companies can find especial use for them in their car shifting operations not only adjacent but actually on shipboard where the cars to be ship ed or to be debarked are required at times to be shifted about in the holds of the company ships. Thus, portability of the car mover is essential.

Prior mover devices are rarely if ever truly portable machines inasmuch as electric motors are the usual power source requiring provision for the conventional off-on power switch and the electric power cord at each location and also some form of straight gear drive to produce proportionately slower output shaft frequency than what the fixed motor running frequency is.

The present car mover materially reduces or largely overcomes the foregoing disadvantages, employing a captive prime mover thereon reversibly coupled to the load by, and introducing its tractive effort through an infinitely variable ratio hydraulic transmission, thus rendering the device truly portable and productive of a very flexible range of self-sustaining operation. The general organization of the car mover is disclosed and claimed in copending Stewart parent application Serial No. 770,103, filed October 28, 1958 and now Patent No. 2,989,007, from which this application is divided addressed to the drive unit comprising the prime mover and hydraulic transmission just noted.

I have shown certm'n presently preferred embodiments of the invention in the accompanying drawings, in which:

FIGURE 1 is a fragmentary side view of a railway car to which the device of the present invention is shown applied;

FIGURE 2 shows a portion of FIGURE 1 in side elevation to enlarged scale;

FIGURES 3 and 4 are rear end elevational and top plan views of the device of FIGURE 1;

FIGURES 5, 6 and 7, respectively are sectional views taken along the respective lines V-V, VI-VI, and VlIVll in FIGURE 2;

FIGURE 8 is a schematic diagram of the transmission apparatus of FIGURE 2.

More particularly in FIGURES 1, 2 and 3 of the drawings, the present car mover device generally indi cated at it} is shown applied to a freight railway car 12 of standard construction supported on two rails 14 of standard track. The car 12 has the usual front and rear wheel trucks of which the rear one 16 is particularly shown and which carry opposed pairs of standard flanged wheels 18, each pair being integrally connected by means of the usual solid axle 29 between wheels. These wheels are provided with the usual manually-operated brakes which are controlled through a brake hand wheel 22 3,120,741 Patented Feb. 11, 1964 located at some convenient point on the rear of the car 12 in association with the usual fixed brake-operating platform 24 or equivalent.

The car mover device 10 has a motor stand 26 mounted to the carriage thereof and supporting a source 28 of prime power, preferably a small single-cylinder gasoline engine with spark ignition. Engine power drives a reduction gear 30 which through a conventional connection 32 is coupled to a transmission input shaft 34. An intervening, timing-type cog-belt 36 which is mounted on appropriate toothed pulleys known as timing belt pulleys further connects the reduction gear 30 to a speed control and reverse unit 38. A high pressure, positive displacement pump at (FIGURE 3) on the motor stand 26 is connected through hydraulic lines to a set of three hydraulic torque booster motors 42 which are controlled as to their speed and direction by means of a cog-belt 44 common thereto which is driven by the speed control and reverse unit 38. An overload slip-clutch can be provided as a precaution in the output shaft of the unit 38 to prevent the transmission of excessive torque. A satisfactory make of belt at and 44 is known as a Gilmer timing belt, made with a rubber or neoprene or other flexible elastomeric backing carrying fabric faced teeth and manufactured by U.S. Rubber Company, New York 20, New York.

A common output member 46 from the torque booster motors 42 has sprocket teeth connected through a drive sprocket chain and sprocket connection 48 to a traction drive output shaft St'ia. The traction drive output shaft 5th: hereinafter described in further detail is journalled for rotation in a main carriage frame member 52 to which a second frame member 54 is adjustably joined at the front for relatively extensible and contractive movement thereto by means of a pair of hydraulic cylinders 56 disposed one at each side of the main frame member '52.

The rear frame member 52 further carries a control stand 8t? (FIGURES 2 and 3) for supporting the speed control and reverse unit 38, which unit carries an upstanding zeromax. speed control lever 82 which pivots between two extremes of position controlling the torque boost motors 42 at an infinitely variable speed ratio. Another upstanding lever 84 pivoted to the unit 38 constitutes a fen-rev. selector handle which determines the direction of rotation taken by the cog-belt 4dand likewise the direction of rotation taken by the torque boost motors 42.

A control harness cable 86 (FIGURES 1 and 2) contains a set of three Bowden slide wires, one constituting an on-otf ignition control wire 8, another 90 being connected to operate the for.-rev. selector handle lever 34, and the third one 92 being connected to the zero-max. speed control lever 82. At its free end, the cable harness 86 carries a remote control device 94 provided with a hand grip as and carrying slidable positioning elements 93 which are connected for hand operation of the Bowden slide wires 88, 9d and 92 respectively. In this way, the operator from a remote vantage point such as from aboard the brake-operating platform 24 of FIGURE 1 cannot only control the brake hand wheel 22 but also by conveniently inserting his hand indicated at 1% in a control carrying position on the back of his hand, he can thus manipulate the elements d8 with the opposite hand to control speed, direction, and stopping of the applied power from the source 28. The fingers of the hand ltltl carrying the remote control remain free to operate the hand wheel.

Each of the frame members 52 and 54 carries an individual grooved roller 118 adapted to engage the flange 12d of the car wheel 18 at the front and rear. The front one of the pair of rollers 118 is mounted for free turning movement on an axle establishing a fixed axis 121 whereas the rear roller 118 is fast to the traction drive output shaft 50a for rotation on a similar fixed axis 121.

In the car wheel moving position of FIGURES 2 and 5, the wheel periphery of the car wheel 13 does not make fiat surface contact with either grooved roller 118; but instead, the protruding flange 120 on the wheel 18 provides reentrant angle engagement with the groove in the roller to intensify their interface of contact against slippage. The two points of contact are in a plane laterally offset inwardly from the plane of the associated rail 14 and the car wheel 18.

Each grooved roller 118 is preferably forged integrally with its associated shaft, and in the case of the rear grooved roller 118 as viewed on the left in FIGURE 2 the integral axle 50a carries a traction drive sprocket 144. The sprocket 144 is made fast to an end extension of the shaft 50a by means of a key 146 and at the periphery it is in constant mesh with the traction drive chain 48. Thus, input torque applied by the engine source 28 is delivered through the sprocket-connected rear roller 113 to a point as far out as possible on the wheel 18, namely, at the outside diameter of its peripheral flange 120.

In FIGURES 2 and 6, the cable harness 86 consists of an assembly of the parallel Bowden slide wires 88, 90 and 92, each of which is made of wire rope strands and which slides in a conventional helically wound guide conduit 152. The guide conduits 152 are individual metal parts molded in a common plastic body 1154 holding them in the properly spaced apart relationship and at the same time imparting the proper flexibility to the cable harness 86.

In FIGURES 2 and 7, the remote control 94 consists of a tubular hollow case 156 in which the Bowden wire operating elements 98 are mounted in individual longitudinally extending slots 158 which are spaced 120 apart. In the embodiment illustrated, the ignition grounding wire 88 is moved by the associated element 98 between an off position at one extreme of travel of the latter and an on position at the opposite extreme. The for.-rev. wire 90 is moved from a neutral center position by the associated element 98 into the opposite extremes of travel of the latter corresponding to forward movement and reverse movement of setting for the transmission. The zero-max. connected wire 92 is moved by the element 98 from a zero-speed position at one extreme of travel of the latter into a maximum speed opposite extreme of travel and the range of adjustability therebetween represents selected speed positions for operating the torque booster motors 42 during constant running speed of the prime mover 28.

In FIGURES 3, 4 and 8, the constantly operating pump 40 which is coupled at 32 to the prime mover reduction gear 30 is hydraulically connected through a filter 168 on its suction side to a hydraulic fluid reservoir 170 (FIG- URE 11). A pressure line 172 supplies the pump output through a terminal branch 174 which under high speed running conditions in general, and always under low torque operating conditions, feeds the entire output to the torque booster motor 42 appearing on the extreme left in FIGURE 8. A relief valve 176 which is normally closed is arranged so as to open a return line 178 leading back to the reservoir 170 when the venting of excessive pressures is required in the line 172. Exhausted fluid from the left hand booster motor 42 feeds as required through a check valve 180 into the next booster motor from which exhausted fluid passes as required through another check valve 182 into the final booster motor and back through the return line 178.

One suitable make of the three motors 42 is type S-l04 torque booster manufactured by Char-Lynn Company of Minneapolis, Minnesota, and described in their booklet Form No. TA-257 and in United States Patent No. 2,821,171, although other known hydraulic transmission units may satisfactorily be employed. However, in that make and type, the basic mechanism which is commonly known as the gerotor thereof consists of inner and outer,

lobed rotary pump elements of which the number of lobes or teeth on the inner and outer elements differs by one. Briefly, the outer element is fixed and the inner rotor revolves around same within the motor in a circular path after the general manner of planetary gearing. The speed control and reverse unit 38 in the illustrated embodiment is connected through the cog-belt 44 so as to rotate speed input shafts 184 provided of the booster motors 42 either forwardly or reversely or hold them stationary depending on the rotation desired of their gerotor-driven output shafts 186. A suitable form for the s eed control and reverse 38 is a model 142 XR zero-max. made by Revco, Inc., Minneapolis, Minnesota, and the purpose thereof is to operate the rotary internal control valve sleeves, not shown, within the motors 42 so as to set the direction and speed controlling ports in proper relation to the output shafts 136 as they are driven.

It is essential that the cog-belt 44 maintain the rotary internal control valve sleeves referred to in absolute synchronism to keep the motors 42 precisely timed to one another for maximum concerted effort. The teeth on the belt 44 are accurately spaced apart and they mesh with axial grooves (of the same pitch, tooth width, and horsepower capacity) formed on the faces of the four identical toothed pulleys over which the belt 44 is trained according to FIGURE 8 and which are also appropriately known as timing belt pulleys. Preferably, the output toothed pulley of the unit 38 has adjustable securing means making it fast to the associated shaft of the unit 38 and of necessity the remaining toothed pulleys on the input shafts 184 each have set screws or other adjustable securing means making them fast to those shafts in precisely timed relation to one another. The three output shafts 186 from the thus coordinated motors 42 mutually drive a sun and pinion gear cluster 188 in which the common sun is connected through the output sprocket 46 to drive the chain 48 and the traction drive shaft 50a.

Following is an example of the dimensions, speeds, and effective torque-multiplication ratios selected within the infinitely variable speed reducer transmission of the device 10 of FIGURES 1 and 8:

Spark ignition engine 28 Briggs & Stratton, single cyl., 2% hp., 4 cycle engine.

Gear ratio speed reducer 30 6:1 reduction. Sheave ratio for cog-belt 36 1.66:1 reduction. Sheave ratio for cog-belt 44. 1:1 ratio. Pitch radius rear grooved drive roller 118 1.5 inches. Sprockets carrying drive chain 48 1:1 ratio. Engine 23 speed 3600 rpm. Pump 40 speed 600 r.p.m.

47.1 linear f.p.m. 3 /2" stroke.

Car speed, max. Hyd. cyls. 56

In operation of the hydraulic system of FIGURE 8, the pressure line 172 makes available a continual flow of pressure fluid to the motors 42 which in their zero speed condition consume no fluid and which therefore enable the valve 176 to Vent the pumped fluid directly into the return line 178 for recirculation. Under the lowtorque operating conditions referred to, the left hand motor 42 rotates in the proper direction so as to consume all the high pressure fluid. Under high load conditions incident to starting a car against full static friction or otherwise, pump pressure in the line 172 builds up to a point at which it will operate a valve 190 which is set so as to be pressure operated and open at a pressure slightly less than 1000 p.s.i. for instance. A companion valve 192 may be set to operate at a point slightly above 1000 p.s.i. in which instance a substantial portion of the pressure fluid is bypassed by the two valves 190, 192 in a manner enabling one third to go to each motor 42 collectively and exert full torque on the sun and planet gearing 13%.

As starting resistance of the load decreases with rising speed, the valve 192 will be the first one to close as the pressure in the line 172 drops and thereafter the two booster motors 42 still operating receive a proportionate share more (i.e., /6 more) of the pump output so as to run slightly faster. As line pressure further decreases due to decreasing load resistance, the valve 190 then closes and the full pump output is delivered to the left hand booster motor 42; this result of the entire oil volume going to one motor therefore produces maximum speed possible. Conversely, the pressure operated valves 190 and 192 automatically operate in that order to place the center motor 42 and then the right-hand motor 42 back on the line as speed decreases and load increases. This two-stage automatic speed change in response to the load demands occurs both in forward drive and in reverse drive of the transmission so as to give three speeds each way for any given setting of the zero-max. connected wire 92. To slow the car in an emergency, the operator can at will put full reverse torque on the driven wheel; and the hydraulic liquid principle in the present transmission readily adapts it to make the transition with only a fraction of the shock, if any, on the machinery when compared with the straight gear drives of the prior art devices.

While I have described certain presently preferred embodiments of my invention, it is to be understood that they may be otherwise embodied within the scope of the appended claims.

I claim:

1. A power transmission system having a power input and a power output shaft comprising,

(A) a rotary pump for supplying fluid under pressure,

(B) a plurality of hydraulic motors,

(1) each connected to said pump to be driven by fluid under pressure from said pump,

(2) each motor having a rotary control valve,

(3) each motor having an output shaft,

(C) a speed control and reverse unit,

(1) said unit having a rotating input shaft connected to said pump,

(2) said unit also having an output shaft connected to said rotary control valves,

(D) manually operated levers in said speed and control unit for controlling the direction and speed of the output shaft of the unit,

(E) means connecting the output shaft of each of said motors to said transmission power output shaft, and

(F) valves controlling the supply of fluid under pressure to said motors in sequence in accordance with the load imposed on said motors.

2. A power transmission system as described in claim 1 in which the valves for controlling the supply of fluid under pressure to said motors in sequence are biased to open at predetermined pressures.

References Cited in the file of this patent UNITED STATES PATENTS 1,939,113 Ferris Dec. 12, 1933 1,994,974 Wiedmann Mar. 19, 1935 2,370,526 Doran Feb. 27, 1945 2,374,588 Doran Apr, 24, 1945 2,627,762 May Feb. 10, 1953 2,846,849 Levetus et a1 Aug. 10, 1958 2,860,713 Peterson Nov. 18, 1958 

1. A POWER TRANSMISSION SYSTEM HAVING A POWER INPUT AND A POWER OUTPUT SHAFT COMPRISING, (A) A ROTARY PUMP FOR SUPPLYING FLUID UNDER PRESSURE, (B) A PLURALITY OF HYDRAULIC MOTORS, (1) EACH CONNECTED TO SAID PUMP TO BE DRIVEN BY FLUID UNDER PRESSURE FROM SAID PUMP, (2) EACH MOTOR HAVING A ROTARY CONTROL VALVE, (3) EACH MOTOR HAVING AN OUTPUT SHAFT, (C) A SPEED CONTROL AND REVERSE UNIT, (1) SAID UNIT HAVING A ROTATING INPUT SHAFT CONNECTED TO SAID PUMP, (2) SAID UNIT ALSO HAVING AN OUTPUT SHAFT CONNECTED TO SAID ROTARY CONTROL VALVES, (D) MANUALLY OPERATED LEVERS IN SAID SPEED AND CONTROL UNIT FOR CONTROLLING THE DIRECTION AND SPEED OF THE OUTPUT SHAFT OF THE UNIT, (E) MEANS CONNECTING THE OUTPUT SHAFT OF EACH OF SAID MOTORS TO SAID TRANSMISSION POWER OUTPUT SHAFT, AND (F) VALVES CONTROLLING THE SUPPLY OF FLUID UNDER PRESSURE TO SAID MOTORS IN SEQUENCE IN ACCORDANCE WITH THE LOAD IMPOSED ON SAID MOTORS. 